Table 2. Theme 1.

The chronic disease frame.

Subtheme	Concept	Exemplary quotes
Impact of condition on daily life and identity	Condition as core feature of identity	…I’ve only really lived life with [T1D]…so I don’t really know what I’m missing. (18-year-old male with T1D) …[Diabetes is] a huge part of my life. I wake up every morning, I test my blood sugar. Like depending on that I’m either feeling awful or great if it’s high or low or perfect…my whole life kind of revolves around trying to keep it as good as I can. (19-year-old male with T1D) I mean I grew up wanting to do different stuff but just never being able to do it [because of my arthritis]. Like I wanted to do gymnastics when I was little. But you know like I think if I didn't have arthritis I'd be doing different things. But I grew up with arthritis so I don't really know. (17-year-old female with JIA)
	Illness intrusiveness	…I've missed a lot of days of school in the past. Like, I've missed 60 days because of arthritis. It was a little hectic. (16-year-old male with JIA) When I’m not feeling well or I’m stuck in the hospital, I’m not really going to get a chance to change my outlook on life. (17-year-old male with IBD) A lot of the time I didn't feel like necessarily going out to do anything [because of my health] …if I just really wasn't feeling up to it, I'd tell [my friends] "I can't" or "I'm feeling really sick."…I kind of felt like maybe people were doubting whether or not I was actually sick all the time. (17-year-old male with IBD)
	Conceptualizing healthy as being symptom and complication free	Being healthy for [my friends] is just exercising and eating healthy. Whereas for me it’s having the full energy to do stuff and make sure there are no flares. (19-year-old female with IBD) To me I guess [being healthy] would be just being able to …kinda just do your everyday life without something getting in the way all the time. (19-year-old female with JIA) I think healthy is kind of like when your body is working the way it should. Like you're not sick, you can do whatever you need to do in a day without an issue. (18-year-old male with T1D)
	Coming to terms with having disease	You just have to realize that things can get better but you have to take all the medications that are prescribed to you …I think I just realized like how severe the illness was. (19-year-old female with IBD-associated arthritis) …I had a decision to make: that I could let diabetes run my life or I could run my life. (18-year-old female with T1D)
	Accelerated or interrupted maturity	[I’m] probably honestly more …mature [than my peers]. I think because I had to grow up at such a young age. And I find myself not finding the same things funny and not really into the whole partying…it’s almost like I just skipped a couple years. (19-year-old female with JIA) I had to mature a little faster [than my friends]…I mean, [Crohn’s is] kind of an adult thing to have to deal with. (19-year-old female with IBD) When Crohn's first hit me, it was kind of during a time when I was becoming a teen, so I didn't really mature as much then. But once I wasn't affected by the Crohn's so much, then I kind of went through it faster. (17-year-old male with Crohn’s)
Health-conscious influences on substance use decisions	Consideration of consequences on chronic condition	…I always thought about how [drinking] would affect my Crohn’s. I’ve always heard about like alcohol can disturb the stomach lining. Therefore I was like, well, if my stomach’s already affected, why add poison to it? (19-year-old male with IBD) I think because [managing my arthritis] consumes so much of my life that I wouldn’t want to just like throw it away in one night [of drinking]. (19-year-old female with JIA) If you drink way too much and you don’t give yourself enough insulin, you wake up and your blood sugar is way too high and you feel like crap. (17-year-old male with T1D) When you are drunk…God forbid if I get sick enough that I’m like throwing up, that’s like always scary because you never know what’s going to trigger this disease because there isn’t concrete stuff on it in terms of food or whatever. (19-year-old female with IBD)
	Consideration of alcohol-medication interaction consequences	I know I can't really skip [my medication] because then my knees are going to hurt really bad. So I guess if I ever drink in the future, I'll just barely have any because I'm afraid that it's going to like cancel it out or something. (16-year-old female with JIA) When I was diagnosed like I felt really sick, like couldn't walk or anything. If I do [drink alcohol] and the medicines stop working, I don't want to go back to where I was. I'd rather just stick with the medicine and have it work. (16-year-old female with polymyositis) Other people can just get black-out drunk and they're fine the next day, but I know I could absolutely never do that [because of my medication]. And it's hard because you do those kind of things to like, relieve stress, but those kind of things actually stress me out more because I know that like, if I'm doing it, it's always risky [because I’m taking methotrexate]. (18-year-old female with JIA)
	Conditioning abstinence on perception of disease activity	If one day I’m planning on going out with my friends and my stomach hurts…I won’t drink…I always listen to my body. (19-year-old female with IBD) Well I [decided not to drink that night because I] was just listening to my body, I guess. I didn't feel great. You know, when my blood sugar’s pretty high like that I just don't feel good at all. I feel like, dehydrated, and I just feel kind of sick. So you know once I start feeling like that, I really try to focus first on getting my blood sugar in check so I can feel better first and then go back to whatever I was doing. (19-year-old male with T1D)
	Valuing clear-headedness to accurately perceive feedback about disease activity and symptoms	It’s just all about feeling if you’re high or low. And you can lose that if you get too drunk. (18-year-old male with T1D) So when people drink alcohol, I don't think they are going to pay attention to their symptoms. Because the brain is not in place to pay attention to what they are doing …I like to have the knowledge of what I'm doing. (17-year-old male with T1D) [When I smoked marijuana] I thought I couldn’t breathe. [My friends] weren't sure what to do because they weren’t sure if it was just because I had you know, had [marijuana] in my system, or like was it because I'm actually hurt and slowly not being able to breathe. (19-year-old female with asthma) When you are drunk, you don't feel things as strongly as like other times …because those feelings are kind of lessened, I’m not as able to be like, “well this is feeling…” you know something like that. (19-year-old female with IBD) Yeah, [I’ve given] a lot of thought [to how my body might react when drinking], actually ‘cause like you can’t trust other people to know what’s happening to your body so you have to be able to tell for yourself. (17-year-old female with T1D)
	Using substances for symptom relief	[Marijuana] like killed my Crohn’s pain…I noticed that out of all the pills I did, me smoking marijuana in a five-year span, I’ve had far less hospitalizations, far less attacks, so I pretty much just stuck with it. (19-year-old male with IBD) …I smoked because it would make my knees stop hurting or help me sleep because I usually can’t sleep at night. (16-year-old-female with JIA) …when you have arthritis, like everything is so tight…and when you drink it’s just sort of like you’re more loose. (18-year-old female with JIA) If I know I'm feeling like my stomach's like upset and I'm having like loose stool and whatnot it’s like, oh, well maybe if I try to smoke maybe this will help. (19-year-old female with IBD-associated arthritis)